I apologize, I assume everyone knows what an HE round is. In my former life I was a howitzer crew chief, HE = High Explosive, fuses are manually applied depending on the mission.

It gets real boring sometimes and every once in a while Soldiers do stupid things like placing razor blades between the fuse and the round. When fired, this in turn causes a zip sound similar to an incoming round. This usually only takes place when green LT's hit the field the first time, insert evil grin!

My theory is that in larger smoothbore barrels, the air pressure from the rear of the round can actually spin the FS backwards until it leaves the barrel and the air pressure of it going forward thru air causes it to spin in the correct direction.

One of my other "hobbies" is roasting my own coffee using a popcorn air popper, and today, while I was roasting another batch, I remembered this comment.

Wouldnt it be possible to design a bolt that pushes air in a way that makes the fins turn the right way?